Portable electronic devices such as, for example, mobile cellular telephones, include a removable battery pack providing electrical power. Such battery packs consist of more than simply a case and battery cells. Indeed, such battery packs may include built-in microprocessor controllers and/or memory circuits used for controlling the charging and discharging of the battery cells.
As battery capacity increases and various battery chemistries require circuitry for safety and performance, the need for better communication with the battery, control of the battery, and reduced power drain internal to the battery pack increases. Some of these features have been addressed with prior battery pack designs. These designs utilize numerous electrical and mechanical contacts which connect to the electronic device or a separate charger. Prior solutions were effective in larger products but become more difficult to implement as the electronic devices and battery packs shrink in size. Also, these functions are not operative when the battery pack is separated from the electronic device. As a result, a charger or device cannot interrogate a battery for its state of charge and warn the user if the battery has been sitting unused for an extended period if it is not connected to the charger or electronic device.
The present invention is directed to overcome one or more of the problems discussed above in a novel and simpler manner.